Seven new species of Lasioglossum (Dialictus) Robertson, 1902 (Hymenoptera: Halictidae: Halictini) from the Yucatán Peninsula, Mexico Author Landaverde-González, Patricia CFEE1568-9AD9-4531-885D-EBF3F68ABB43 General Zoology, Institute for Biology, Martin-Luther University Halle-Wittenberg, Hoher Weg 8, 06120 Halle (Saale), Germany. patricia.landaverde@zoologie.uni-halle.de Author Gardner, Joel AA15FE6E-921A-46D6-BC67-88E067F283D9 Department of Entomology, University of Manitoba, 12 Dafoe Rd., Winnipeg, Manitoba, R 3 T 2 N 2, Canada. clickbeetle3364@gmail.com Author Moo-Valle, Humberto 35656D9E-491C-4C34-8CAD-069E4B9F0E9B Departamento de Apicultura Tropical, Campus Ciencias Biológicas y Agropecuarias, Universidad Autónoma de Yucatán, Mérida, Mexico. moovalle@correo.uady.mx Author Quezada-Euán, José Javier G. BD9DBC7E-AD59-47BA-BA72-4A881A31E320 Departamento de Apicultura Tropical, Campus Ciencias Biológicas y Agropecuarias, Universidad Autónoma de Yucatán, Mérida, Mexico. javier.quezada@correo.uady.mx Author Ayala, Ricardo B1CFBA3B-C28B-40C5-B674-CBC8DB69418C Estación de Biología Chamela, Instituto de Biología, Universidad Nacional Autónoma de México (UNAM), Apartado Postal 21, San Patricio Jalisco, 48980, Mexico. rayala@ib.unam.mx Author Husemann, Martin D31A05CA-DCD8-4CFB-A9D0-E9F070EC4707 Centrum für Naturkunde, University of Hamburg, Martin-Luther-King-Platz 3, 20146 Hamburg, Germany. martin.husemann@uni-hamburg.de text European Journal of Taxonomy 2023 2023-03-22 862 1 1 65 http://dx.doi.org/10.5852/ejt.2023.862.2079 journal article 264116 10.5852/ejt.2023.862.2079 957e3c13-6dd3-4b13-9576-9f013a4990bc 2118-9773 7767855 5D38246E-B144-434C-A2FE-C303381B0CD7 Lasioglossum ( Dialictus ) exiguum ( Smith, 1879 ) Figs 22A , 23A , 24A , 34A Halictus exiguus Smith, 1879: 37 ( holotype , , NHMUK 010265368). Dialictus exiguus Moure & Hurd 1987: 100 (catalogue). Type material Holotype MEXICO ; on/around Orizaba volcano; [ 19° N , 97.3° W ]; “8.M.1856”; M. Salle leg.; NHMUK 010265368 . Other material examined MEXICO Quintana Roo 1 ♀ ; 12 km NW of Reforma ; [ 18.89° N , 88.65° W ]; 14 Oct. 1986 ; Charles D. Michener leg.; SEMC SM0753053 2 ♂♂ ; same collection data as for preceding; 14 Oct. 1986 ; Charles D. Michener leg.; SEMC SM0730146 , SM0753052 1 ♀ ; Reforma ; [ 18.81° N , 88.57° W ]; 14 Oct. 1986 ; Charles D. Michener leg.; SEMC . Remarks Uncommon on the Yucatán Peninsula ( four specimens examined in the region); more common in Veracruz . The very large head and rectangular, strongly toothed clypeus apical margin are unmistakable diagnostic characters for this species. We consider the identifications highly reliable despite the distance between Orizaba and Quintana Roo .